How to import txt files with variable column number with textscan ?

I use textscan to import txt files mixed with string and numbers. Usually these files have 50 columns. The first line is the header. I can make the string column the last column in the data file. My code is below. Now the data files vary in column numbers. I can check the tokens size for the column numbers. But I don't know how to make my text scan more flexible to handle variable column sizes.

fid = fopen(filename,'rt');
tline = fgetl(fid);
tokens = regexp(strtrim(tline), ',', 'split');
a = textscan(fid,'%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%q','Delimiter',',','EmptyValue',NaN); 

fclose(fid);

Thank you, Jane

Answer 1

[per isakson]

"check the tokens size for the column numbers" &nbsp thus

    ncol = number_of_columns

and

    a = textscan( fid, [ repmat('%f',[1,ncol-1]), '%q' ] ...   
                , 'Delimiter',',', 'EmptyValue',NaN );

and why not use

    'CollectOutput', true

Answer 2

[Jane]

Thank you, per isakson. I know there must be an easy way instead of putting 50 %f. Thank you, it is very helpful.